nerdgineer
Flashlight Enthusiast
AlexGT asked about whether there were any 1xCR123 lights driving a PR base bulb so he could use it for a SMJLED bulb. I don't know of any, but I did make an interesting discovery: the 87 cent 2AA Walmart flashlight (get the one with a faceted reflector) is fat enough to hold a CR123 battery easily. The metal ring in the tail prevents you from inserting one from the back, but a CR123 will drop in from the front just fine.
So I thought: why not cut one of those Walmart lights short and make your own? It was SO obvious, even someone with NO modding skills like me might try it.
I took one of the 87 cent lights, pulled off the metal ring at the back, and cut the body off so it extended just about 0.2" past the base of a CR123 resting resting against the bulb base. Most anything will make this cut - I used a steak knife. Be careful cutting through the part of the body behind the switch as it is easy to damage the copper strip running back from the switch. Then pull off the cut off body end LEAVING THE METAL STRIP INTACT.
I took the spring out of the base and soldered a short piece of wire between it and a notch I cut in the copper strip about 1/8"" past the end of the body. I cut off the excess copper strip and folded the strip back into the body so nothing protruded past the base. The result looks like this:
I took a Dremel tool with the coarse drum sander bit and ground away ALL the threads in the tail cap (easy as plastic is soft). Using the end of the body I had cut off, I practiced grinding away at the ribs on the body until I could get a tight press fit between the tail cap and body. Using that practice as a guide, I then ground away the end of the actual body so I could get a similar press fit. The ground down body is shown in the picture above.
Using airplane glue, I then glued the tail cap onto the body like I was doing PVC pipe (put a layer of glue on both surfaces, give it 5 seconds, and then push it on hard while twisting back and forth - it will melt together for a solid and waterproof joint). The result is a very short, very solid, 1xCR123 light which, with the SMJLED PR bulb, puts out close to the light of a L1P with good pattern, good color, and 10+ hours of flat, regulated run time. It tail stands, too.
It is considerably shorter than my Nuwai 2611 CR123 light, is easily pocketable (if a little fat), and cost me all of 87 CENTS! Here it is next to the Nuwai and the normal 2AA body:
I believe the run time is flat because an old CR123 battery rejected by a digital camera runs the light at about 85% the brightness of a new CR123. Incidentally, the fresh CR123 runs the light just a little brighter than 2 fresh AA alkalines according to my meter. Don't know why, maybe less voltage sag with the CR123 or the soldered connection to the spring reduces the circuit resistance compared to the regular AA light's copper ring/spring contact.
Anyway, the 87 cents part makes all this a kick. I can put PDA protector on the lens for pocket carry, or replace it with glass (at a cost of a lot more than 87 cents), or just get a few more lights for spare lenses. Too funny...
I think this is actually a very practical light. Due to the SMJLED bulb's efficiency - it fills a niche not covered by any other light: short, light (45 grams with battery), bright (beats the pants off the 1AA 0,5 watters, close to L1P output), VERY long run time, and cost less than 96 cents (incl. sales tax) plus a little fun time sawing away with a steak knife. It is not waterproof, but if you hold it with the switch down, it should function OK in even the heaviest downpour as the tail is waterproof and the head screws in pretty tightly.
(Update) I covered the excess glue at the tail with some electrical tape. Now it's all pretty....:naughty:
(Update)
Tried some beamshots. Sorry about quality - cramped quarters, first try, vinyl wallpaper, etc. BuckaLite on left with fresh CR123, Fenix L1P on right with fresh nimh. Both lights 9 inches from wall. BuckaLite has considerably wider beam. Fenix is a little warm in color, and BuckaLite a little cool, but not as much as picture makes it look.
Then I moved the L1P further out until the light circles were about the same size. Distortion is from camera wide angle and tight quarters. BuckaLite still at 9", L1P at 12" from wall (below).
When used outside, it looks to me like they have about the same output.
So I thought: why not cut one of those Walmart lights short and make your own? It was SO obvious, even someone with NO modding skills like me might try it.
I took one of the 87 cent lights, pulled off the metal ring at the back, and cut the body off so it extended just about 0.2" past the base of a CR123 resting resting against the bulb base. Most anything will make this cut - I used a steak knife. Be careful cutting through the part of the body behind the switch as it is easy to damage the copper strip running back from the switch. Then pull off the cut off body end LEAVING THE METAL STRIP INTACT.
I took the spring out of the base and soldered a short piece of wire between it and a notch I cut in the copper strip about 1/8"" past the end of the body. I cut off the excess copper strip and folded the strip back into the body so nothing protruded past the base. The result looks like this:
I took a Dremel tool with the coarse drum sander bit and ground away ALL the threads in the tail cap (easy as plastic is soft). Using the end of the body I had cut off, I practiced grinding away at the ribs on the body until I could get a tight press fit between the tail cap and body. Using that practice as a guide, I then ground away the end of the actual body so I could get a similar press fit. The ground down body is shown in the picture above.
Using airplane glue, I then glued the tail cap onto the body like I was doing PVC pipe (put a layer of glue on both surfaces, give it 5 seconds, and then push it on hard while twisting back and forth - it will melt together for a solid and waterproof joint). The result is a very short, very solid, 1xCR123 light which, with the SMJLED PR bulb, puts out close to the light of a L1P with good pattern, good color, and 10+ hours of flat, regulated run time. It tail stands, too.
It is considerably shorter than my Nuwai 2611 CR123 light, is easily pocketable (if a little fat), and cost me all of 87 CENTS! Here it is next to the Nuwai and the normal 2AA body:
I believe the run time is flat because an old CR123 battery rejected by a digital camera runs the light at about 85% the brightness of a new CR123. Incidentally, the fresh CR123 runs the light just a little brighter than 2 fresh AA alkalines according to my meter. Don't know why, maybe less voltage sag with the CR123 or the soldered connection to the spring reduces the circuit resistance compared to the regular AA light's copper ring/spring contact.
Anyway, the 87 cents part makes all this a kick. I can put PDA protector on the lens for pocket carry, or replace it with glass (at a cost of a lot more than 87 cents), or just get a few more lights for spare lenses. Too funny...
I think this is actually a very practical light. Due to the SMJLED bulb's efficiency - it fills a niche not covered by any other light: short, light (45 grams with battery), bright (beats the pants off the 1AA 0,5 watters, close to L1P output), VERY long run time, and cost less than 96 cents (incl. sales tax) plus a little fun time sawing away with a steak knife. It is not waterproof, but if you hold it with the switch down, it should function OK in even the heaviest downpour as the tail is waterproof and the head screws in pretty tightly.
(Update) I covered the excess glue at the tail with some electrical tape. Now it's all pretty....:naughty:
(Update)
Tried some beamshots. Sorry about quality - cramped quarters, first try, vinyl wallpaper, etc. BuckaLite on left with fresh CR123, Fenix L1P on right with fresh nimh. Both lights 9 inches from wall. BuckaLite has considerably wider beam. Fenix is a little warm in color, and BuckaLite a little cool, but not as much as picture makes it look.
Then I moved the L1P further out until the light circles were about the same size. Distortion is from camera wide angle and tight quarters. BuckaLite still at 9", L1P at 12" from wall (below).
When used outside, it looks to me like they have about the same output.
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